Which one of the following drug causes increased concentration of Na' & CI- in urine with normal bicarbonate -

Ans. is 'a' i.e., Ethacrynic Acid Ethacrynic acid is a loop diuretic and acts by inhibiting No' - - 2Ct transpo in ascending loop of Nettle. Thus it inhibits reabsorbtion of No' and Ch ions and promotes excretion of these electrolytes in urine. Unlike other loop diuretics however, it does not inhibit carbonic anhydrase, and therefore it does not cause any increase in WO jexcretion in urine. Remember o Most marked Kaliuresis (K' excretion) is caused by : Acetazolamide o Most marked Natriuresis (Natexcretion) is caused by : Furosemide o Most marked Chloride excretion is caused by : Ethacrynic acid : Acetazolamide (Pretest) o Only diuretic which inhibits choride excretion is that is why it causes metabolic acidosis. : Thiazide like diuretics e.g. indapamide, metazoline, chlohalidone. o Diuretics which do not promote bicarbonate excretion : Ethacrynic acid o Diuretics which maximally promotes uric acid excretion : Acetazolamide (by alkalanizing urine)